Review on research status and development trends of solar radio spectrometers

Abstract

Intense solar activity is a major driver of hazardous space weather. The associated processes, including strong electromagnetic radiation, plasma ejections, and high-energy particle acceleration, can significantly disturb the Sun-Earth environment within a short time and further trigger a series of chain effects such as ionospheric disturbances and high-frequency communication interruptions, thereby posing serious threats to critical sectors including aviation, aerospace, and telecommunications. With the continuous advancement of space technology, society has placed increasingly higher demands on space-weather monitoring with high accuracy and reliability. Consequently, the development of high-performance solar radio observing systems has become an important approach to improving space-weather forecasting and mitigation capabilities. In solar physics, radio emissions at different frequencies correspond to radiation mechanisms occurring at different heights and under different plasma-density conditions in the solar atmosphere. Therefore, obtaining observational data with the broadest possible frequency coverage is not only crucial for revealing the acceleration mechanisms of high-energy electrons in solar flares, but also provides important support for understanding the spatiotemporal evolution of solar eruptions. From the perspective of instrumentation development, it is thus of great significance to establish solar radio observing systems with broader frequency coverage and higher temporal and spectral resolutions. This paper systematically reviews the development of solar radio observing instruments worldwide, summarizes the structural characteristics of representative radio telescopes and spectrometers from the decimeter, centimeter, to millimeter wavelength bands, and compares their system designs, signal-processing chains, and frequency coverage. On this basis, the current status of solar radio observing facilities is analyzed, and the key technical bottlenecks and future development trends are discussed. It is hoped that this review will provide useful references for the planning, design, and key-technology development of future solar radio observing systems.

Keywords

solar physics / radio observation / instrument development / radiometer / broadband spectrometer / signal processing

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Funding

National Natural Science Foundation of China(42127804)

National Natural Science Foundation of China(12433013)

National Natural Science Foundation of China(42374219)